1. Field of the Invention
The present invention relates to compounds for the suppression of foaming in yeast fermentation without the inhibition of yeast growth or the premature softening or liquefaction of the yeast when compressed.
2. Description of Related Art
It is known that yeasts, particularly baker's yeast, are industrially produced by the fermentation of molasses. Troublesome foaming can occur to a considerable extent during the fermentation process, particularly where it is carried out in modern, high-output fermentation plants. This foaming has to be suppressed by the addition of defoamers.
Now, in recent years, yeast manufacturers have complained that baker's yeast changes its consistency in storage, ultimately becoming soft or even liquid and hence unsaleable. The reduced yeast quality is blamed by the yeast industry on the increasing surfactant content of the molasses.
It has now been found that the consistency of baker's yeast is influenced by the nature of the foam inhibitor and that all the yeast defoamers hitherto available on the market or proposed for this purpose lead to more or less rapid softening of the yeast.
Accordingly, there is a considerable need for a defoamer which, even in small quantities, prevents troublesome foaming during the fermentation of yeast, has very little inhibiting effect on the growth of the yeast cultures and does not result in softening or liquefaction of the final yeast over a reasonable period of storage. This problem is solved by the present invention.